Question

honors biology - lactose intolerance
provide a neatly typed, spell - checked response to the following questions. completed response are due at the start of class on tuesday, october 14th. (15 points)

• why does lactose intolerance (the inability to digest lactose) increase with age in most mammals? (5pts.)

lactose intolerance increases with age in most animals because their bodies naturally stop producing the enzyme lactase after they are weaned from milk.

• what mammals (besides certain human groups) are the exception to this and why? (5pts.)

Explanation:

1. For the first question, in most mammals, lactase - the enzyme needed to digest lactose - production naturally stops after weaning from milk, which leads to increased lactose intolerance with age.
2. For the second question, some domesticated animals like cats and dogs can sometimes tolerate lactose to an extent. This is due to selective breeding and adaptation to human - provided diets that may include dairy products in small amounts. Also, some mammals that have a diet consistently including lactose - containing substances may have evolved to maintain lactase production.

Answer:

• For the first question: In most mammals, the body stops producing lactase after weaning from milk, causing increased lactose intolerance with age.
• For the second question: Some domesticated animals like cats and dogs can be exceptions to an extent due to selective breeding and diet - related adaptation. Also, mammals with diets consistently including lactose - containing substances may have evolved to maintain lactase production.